Wrinkled nanoporous gold films with ultrahigh surface-enhanced Raman scattering enhancement.

WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
ACS Nano (Impact Factor: 12.03). 06/2011; 5(6):4407-13. DOI: 10.1021/nn201443p
Source: PubMed

ABSTRACT Amplified by plasomonic nanostructured metals, Raman intensity of organic molecules and biomolecules can be dramatically improved, particularly at "hot spots" where intense electromagnetic fields are produced in the vicinity of narrow nanogaps between metallic nanostructures. Therefore, developing new substrates with a high density of "hot spots" has been the recent topic of intense study. Here we report wrinkled nanoporous gold films that contain abundant Raman-active nanogaps produced by deformation and fracture of nanowire-like gold ligaments. This novel nanostructure yields ultrahigh surface enhanced Raman scattering for molecule detection.

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